Are DNO cables in the UK fused before going into a building? And if so how? What happens if you were to short the cable out before the cutout main fuse?
View: https://youtu.be/HQSohl-C_nk?t=180
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Most boards you have to hold the fuse carrier in your hand, insert the bottom contact and hinge it close. Very interesting when locating faults, if it starts rumbling and the transformer dances about DO NOT remove the fuse, hold it in till the fuse blows or the fault clears.
To the best of my knowledge they dont, at the concept stage they work out maximum lenghts and provide that as guidance to the field guys.Can you confirm that the DNO does adiabatic and loop impedance equations so that 25mm2 tap is indeed protected from short circuit?
Yes I was very familiar with break back handles, dident the t3gf3s have the bronze trapeziod fitting though.
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To the best of my knowledge they dont, at the concept stage they work out maximum lenghts and provide that as guidance to the field guys.
Remember also that some of the cables in towns could be up to a hundred years old.
Is there anyway these could be put underground? Does such a thing exist?
I just want to say I'm amazed at the level of fusing.
Can I ask? Why does the UK fuse everything on the DNO side?
Theres plenty of UG subs in London if you know what to look for. Biggest problem is water ingress into the switch gear ,an ocb full of water makes a mess when they trip under fault conditions.Is there anyway these could be put underground? Does such a thing exist?
Underground cables are great until they go wrong...
Central London electrical fire still burning underground - https://www.theguardian.com/uk-news/2015/apr/02/central-london-electrical-fire-still-burning-underground
Yep, and all down to a p.poor maintenance regime .Underground cables are great until they go wrong...
Central London electrical fire still burning underground - https://www.theguardian.com/uk-news/2015/apr/02/central-london-electrical-fire-still-burning-underground
Underground cables are great until they go wrong...
Central London electrical fire still burning underground - https://www.theguardian.com/uk-news/2015/apr/02/central-london-electrical-fire-still-burning-underground
London uses a solid LV network I think it is the only part of the UK to do so. Bit difficult to explain but basically you have about four transformers with HV and LV protection feeding into a solidly interconnected area. Better utilization of copper but very high fault levels, most faults blow clear but can cause a very big bang.
Is that a boyband? Sounds like it caters for all tastes.Are you talking about a network system like Manhattan, Brooklyn and Queens?
Is that a boyband? Sounds like it caters for all tastes.
I have no idea what you do in the colonies.
I have heard of the town called new York City.Wait, you've never heard of New York City?
I don't really know the range, but I think most built up areas have ones in the 500kVA to 1MVA range feeding something like 100-200 homes.Fascinating differences. How many kva is your 11kv-415 volt transformer?
I have heard of the town called new York City.
I haven't heard of the boyband, I take it those three guys are in a boyband called new York city
I don't really know the range, but I think most built up areas have ones in the 500kVA to 1MVA range feeding something like 100-200 homes.
Remote building, farms, etc, probably have ones in the tens of kVA region depending on their needs, but the majority of UK supplies would be in modest-sized networks around a middle-sized substation.
Hopefully others on here with far more DNO knowledge can comment?
Ah so they are like Marchmont, Sciennes, and St Giles' Grange.
Now think about doing it in a small space, with everything around you made of steel, and rolling about at sea ... and oh yes, DCWow - it give me the willies just thinking about working on something like that!
I struggled to spot the details as they zoomed in and out of stuff a bit quick. But yes, out here in the sticks it's normal to have loops. I happen to know that we are fed from 2off 132kV feeders into the substation the other side of town. Those feeders go into 132/33kV transformers and 33kV distribution boards. Then a number of 11kV boards are fed from 33/11kV transformers. Having had a private tour of the new 11kV distribution board before it was commissioned, a typical arrangement has the board in two halves - each fed from the separate 132kV feeders via the 33kV system. There's a link between the two halves, so that a loss of one of the feed can be catered for by opening the feeder and closing the link - otherwise it's left open.You don't got your MV cables in switch loops like Germany (1:00 as an example)?
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